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Old 06-24-2003   #1 (permalink)
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Unanswered: Lowering the rear

How much can you lower the rear end of the GT without screwing up the geometry of the Panhard rod? I would like to chop the rear spring just enough to drop it about an inch, for now. Later on I plan on cutting an end off of the rod, adding a heim joint to make it adjustable, and buying correct lowering springs. So for now, I know this isn't the best way, but I think it should do for just a minor drop. Am I in line?
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Old 06-24-2003   #2 (permalink)
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Lowering rear

As far as I know you can cut the springs and not have any problems. I believe a half coil. I had a rear done like that though, and I didn't really care for it. I felt if the suspension travels far enough the springs could come out or bind when the rear compressed. The sport srings are stiffer rate is all, but no mods to the pan hard rod need to be made. I have also seen this rod bent after the springs were cut....done on purpose????Done by accident????? Not sure
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Old 06-24-2003   #3 (permalink)
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Any lowering of the rear of a GT screws up the already bad rear geometry. Messes up the anti-squat worse than it already is, messes up the panhard bar angle, shifts the rear axle laterally, reduces travel (of course), and reduces the effectiveness of the shocks due to the greater inclination angle. Probably not what you want to hear.....but at least if the car feels 'squirrely' after lowering it, you'll know why.

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Old 06-25-2003   #4 (permalink)
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Wow... where to begin. First cutting the springs makes them stiffer... so if you cut them an inch, then you didn't lower the car an inch 'cause they don't sag as far 'cause they are stiffer.

Cutting springs also requires you cut them exactly the same... assuming that they started out the same. Or if they started out different and you cut them different, they could end up the same... or you could end up EVIL.

Lowering the rear without making appropriate changes to the front can also make it EVIL. With a lower and stiffer rear, the roll center is moved in the rear, but not in the front. EEEVIL

I could go on, but I think you get the idea. Call the Opel GT Source and get springs & sway bars, both front and rear and you will have a balanced car.

And since you mentioned an adjustable panhard bar... I have just finished a "kit" late this afternoon for the rear suspension trailing arms, and panhard bar. Here's a pic
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Old 06-25-2003   #5 (permalink)
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Those are nice pieces! How much are you charging for the set? Probably easier than sourcing all the parts and putting them together myself.
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Old 06-25-2003   #6 (permalink)
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The trailing arms are $85 each including rod-ends, but without the bushings/offset spacers.

The Panhard bar with rod ends and again without bushings is $95.

The trailing arm bushing/offset spacer set has 4 different size spacers per side to accomodate the offset in the chassis to rear end mounts... the set is $85

The panhard bar bushing set is $40.

I am doing all the pieces seperately so folks can repossition the mounts for all of the pieces if they want... especially the panhard bar.

If anyone wants the complete kit, it will be 10% less... or $351
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Old 06-25-2003   #7 (permalink)
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Okay, (Bob and Bob), I get the picture. I was just asking! I'll hold off on lowering the rear until I can do it correctly. Besides, I feel the car is handling very well right now, very neutral....so no need for me to screw it up! I over cooked a slalom on Sunday and lost the rear and I still was able to gather it up before it came around. So I guess I need to work on the driver first....

Bob D, your parts look awesome.

Bestus,
James
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Old 06-28-2003   #8 (permalink)
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Question

How about using a watts linkage in the place of the original panhard rod, I see the guys in Europe use it know of any photos
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